Automatically releasing bathtub overflow stopper

ABSTRACT

Described are devices, systems, and methods for blocking or impeding the flow of fluid through the overflow drain of a bathtub. A device may include a stopper configured to be removably held in place by water pressure or buoyancy only when water level in the bathtub is above at least one overflow opening. The stopper may include a body defining an internal arcuate surface configured to cover the at least one overflow opening. A system may include: a cover plate comprising at least one overflow opening in one of an annular skirt and a domed portion; and a stopper comprising a body defining an internal arcuate surface, the stopper removably held in place by fluid pressure or buoyancy only. A method may include: covering at least one overflow opening with a stopper; and removably holding the stopper in place by fluid pressure or buoyancy only.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of the earlier U.S. Utility Patent Application to J. Jeffrey Gunn entitled “AUTOMATICALLY RELEASING BATHTUB OVERFLOW STOPPER,” Ser. No. 10/806, 757, filed Mar. 22, 2004, now pending, the disclosure of which is hereby incorporated entirely herein by reference.

BACKGROUND

1. Technical Field

This document relates generally to a device, system, and method for blocking or impeding the flow of fluid through an overflow drain of a bathtub.

2. Background Art

Typical bathtubs include an overflow drain which takes the form of a drain opening in a wall of the bathtub and a generally circular cover plate over the drain opening. One typical cover plate cover plate has an annular skirt axially projecting from the perimeter of the cover plate towards the bathtub wall. At the bottom of the cover plate are one or two overflow openings which limit the water level in the tub. Another typical cover plate has a plurality of overflow openings in the face of the of the cover plate. Some persons prefer to take a bath in a nearly full tub, with the water level above the overflow openings, and accordingly desire to block the overflow drain.

SUMMARY

In an aspect, this document features a device for blocking or impeding the flow of water through at least one overflow opening of a bathtub. The device may include a stopper configured to be removably held in place by a pressure differential (e.g. water pressure and/or suction/vacuum) and/or buoyancy only when water level in the bathtub is above the at least one overflow opening. The stopper may include a body defining an internal arcuate surface configured to cover the at least one overflow opening.

Implementations may include one or more of the following. The body may be one of a semi-annular body, a semi-circular body, and a circular body. The semi-circular body may include a semi-disc-shaped front portion surrounded by a semi-annular portion, the semi-annular portion defining the internal arcuate surface. The circular body may include a disc-shaped front portion surrounded by an annular portion, the annular portion defining the internal arcuate surface, and the disc-shaped front portion and the annular portion defining an internal cavity. The internal arcuate surface may be a concave surface. The stopper may include a tether attachment aperture. The tether attachment aperture may be defined in a free end of a handle attached to an external portion of the body. The stopper may be formed of one of a material which has a negative buoyancy in water, a material which has neutral buoyancy in water, and a material which has a positive buoyancy in water. The stopper may be formed of vinyl.

In another aspect, this document features an overflow drain and stopper system. The system may include an overflow drain comprising an overflow drain opening in a wall of a bathtub and a cover plate over the overflow drain opening, the cover plate comprising at least one overflow opening in one of an annular skirt and a domed portion. Further included may be a stopper for blocking or impeding the flow of fluid through the overflow drain. The stopper may comprise a body defining an internal arcuate surface, the stopper removably held in place by fluid pressure or buoyancy only when water level in the bathtub is above the at least one overflow opening.

Implementations may include one or more of the following. The body may be one of a semi-annular body, a semi-circular body, and a circular body. The semi-circular body may include a semi-disc-shaped front portion surrounded by a semi-annular portion, the semi-annular portion defining the internal arcuate surface. The circular body may include a disc-shaped front portion surrounded by an annular portion, the annular portion defining the internal arcuate surface, and the disc-shaped front portion and the annular portion defining an internal cavity. The internal arcuate surface may be a concave surface. The stopper may include a tether attachment aperture. The tether attachment aperture may be defined in a free end of a handle attached to an external portion of the body. The stopper may be formed of one of a material which has a negative buoyancy in water, a material which has neutral buoyancy in water, and a material which has a positive buoyancy in water. The stopper may be formed of vinyl.

In still another aspect, this document features a method for blocking or impeding the flow of fluid through an overflow drain, the overflow drain comprising an overflow drain opening in a wall of a bathtub and a cover plate over the overflow drain opening, the cover plate comprising at least one overflow opening in one of an annular skirt and a domed portion. The method may include: covering the at least one overflow opening with a stopper; and removably holding the stopper in place by a pressure differential (e.g. water pressure and/or suction/vacuum) and/or buoyancy only when water level in the bathtub is above the at least one overflow opening.

Implementations may include one or more of the following. Covering the at least one overflow opening with a stopper having a body defining an internal arcuate surface. Covering the at least one overflow opening with a stopper having one of a semi-annular body, a semi-circular body, and a circular body. Covering the at least one overflow opening with a stopper having one of a negative buoyancy in water, a neutral buoyancy in water, and a positive buoyancy in water. Covering the at least one overflow opening with a vinyl stopper. Tethering the stopper.

The foregoing and other aspects, features, and advantages will be apparent from the DESCRIPTION and DRAWINGS, and from the CLAIMS.

BRIEF DESCRIPTION OF THE DRAWINGS

Implementations will hereinafter be described in conjunction with the appended DRAWINGS, where like designations denote like elements, and:

FIGS. 1-2 are perspective views of an overflow stopper implementation and an overflow drain of a bathtub;

FIG. 3 is a front elevational view of the cover plate of FIGS. 1-2;

FIG. 4 is a bottom plan view of the cover plate of FIG. 3 taken along line 4-4 of FIG. 3;

FIG. 5 is a perspective view of an overflow stopper implementation;

FIG. 6 is a rear elevational view of the overflow stopper of FIG. 5;

FIG. 7 is a perspective view of another overflow stopper implementation;

FIG. 8 is a rear elevational view of the overflow stopper of FIG. 7; and

FIGS. 9-10 are broken away perspective views of the overflow stopper of FIG. 7 in conjunction with an overflow drain of a bathtub.

DESCRIPTION

Referring first to FIGS. 1 and 2, a bathtub 10 includes a top rim 12, a bottom 14, and an end wall 16. An overflow drain opening 18 in the end wall 16 is shown in dash lines. Over the drain opening 18 is a generally circular cover plate 20. The cover plate 20 is attached to a circular mounting plate (not shown). In FIG. 1, the bathtub 10 is filled with water 22 to a water level 24 above the drain opening 18 and above the cover plate 20, as is described in detail herein below. In FIG. 2, the bathtub 10 is empty.

Referring to FIGS. 3 and 4, which are enlarged front elevational and bottom plan views, respectively, of the cover plate 20 in isolation, the cover plate 20 has a circular front portion 30, and an annular skirt 32 which axially projects from the perimeter 34 of the cover plate 20, towards the end wall 16 of the bathtub 10 when installed as shown in FIGS. 1 and 2. When installed, an edge of the cover plate 20 contacts either the bathtub end wall 16 or the circular mounting plate (not shown).

At the bottom 38 of the cover plate 20 there are a pair of overflow openings 40 and 42 or cutouts 40 and 42 in the annular skirt 32 through which bathtub overflow water enters the space behind the cover plate 20 and the drain opening 18. The cutouts 40 and 42 are separated by an intermediate skirt portion 44. The cover plate 20 additionally includes a pair of apertures 46 and 48 for attachment screws 50 and 52 (FIGS. 1 and 2), as well as a central aperture 54 for a drain toggle 56 (FIGS. 1 and 2).

Also visible in FIGS. 1 and 2 and associated with the bathtub 10 are a water supply spout 60, hot and cold water faucet handles 62 and 64, as well as an intermediate shower diverter valve handle 66.

In FIG. 1, a device 70 embodying the invention is blocking or at least impeding the flow of water through the overflow drain of the bathtub 10, in particular is blocking the overflow openings or cutouts 40 and 42 in the annular skirt 32 of the cover plate 20. The water level 24 is above the level of the overflow openings or cutouts 40 and 42, and above the level of the actual drain opening 18.

FIG. 2 illustrates the situation when the water 22 (FIG. 1) has been drained from the bathtub 10, and the device 70 has fallen away from the cover plate 20, more particularly away from the overflow openings or cutouts 40 and 42. However, the device 70 is conveniently retained by a tether 72 looped around a convenient point, in this particular example, the spout 60.

Referring finally to FIGS. 5 and 6, the device 70 more particularly comprises a stopper 70 which, in the illustrated embodiment, has a semi-annular body 80 which includes an internal arcuate surface 82, which may be a concave surface, so as to cover the overflow openings 40 and 42, as well as an external, partially arcuate surface, which may be a partially concave surface. Projecting from the internal arcuate surface 80 are a pair of locating bosses 84 and 86 which are sized so as to fit within the overflow openings 40 and 42, respectively. The stopper 70 has a handle 88 attached to an outside portion of the semi-annular body 80, opposite the arcuate surface 82, and terminating in an aperture 90 for attachment of the tether 72. The stopper 70 is made from a soft pliable plastic, rubber, or rubber-like material, such as a vinyl, and has a neutral or slightly positive or negative buoyancy in water.

It is significant that the locating bosses 84 and 86 function as locating bosses only, and do not fit tightly within the overflow openings 40 and 42. In other words, the locating bosses 84 and 86 are not intended to provide frictional engagement.

The stopper 70 additionally includes edges 92 and 94 which typically contact the cover plate 20 to block or impede the flow of water through the overflow drain, aided by the pliable nature of the stopper 70 material. Thus, depending on the precise shape of the cover plate 20 and the cutouts 40 and 42, at least a partial seal is formed between contacting portions of the concave arcuate surface 82 and the edges 92 and 94, on the one hand, and portions of the cover plate 20, on the other hand. As a result, the flow of water through the cutouts 40 and 42 and then through the drain opening 18 is either blocked or greatly impeded.

A significant characteristic of the stopper 70 is that when the water level 24 in the bathtub 10 is above the overflow openings 40 and 42, the stopper 70, as a result of the material of which it is made and its configuration, is held in place by a pressure differential (e.g. water pressure from water 22 and/or suction/vacuum) and/or buoyancy only. In other words, any frictional engagement which may exist is insufficient to hold the stopper 70 in place without the water 22.

As a result, when the bathtub 10 is being filled with water 22, the stopper 70 must be deliberately employed at the time when the water level 24 just reaches the height of the overflow openings 40 and 42. This prevents a person from applying the stopper 70 to block the overflow openings 40 and 42 while beginning to fill the bathtub 10 with water 22, with the intention of returning to shut off the flow of water 22 into the bathtub before the bathtub 10 overflows. Many persons do other tasks while a bathtub 10 is filling, at least in the initial stages, and accordingly do not simply watch the bathtub 10 during the initial stages of a filling operation. If a person is distracted while the bathtub 10 is filling and if the stopper 70 were to be in place, the bathtub 10 could very well overflow.

Accordingly, during use, when the water level 24 reaches the overflow openings 40 and 42 during a filling operation, the person filling the bathtub positions the stopper 70 as illustrated in FIG. 1 so as to block the overflow openings 40 and 42. At that point, one possibility is that the person manually holds the stopper 70 in place for a minute or two until such time as the water level 24 has sufficiently risen to hold the stopper 70 in place for example. Alternatively, the person at that point may simply turn off the flow of water 22 into the bathtub 10 and enter the bathtub 10. Water displaced by the person's body causes the water level 24 to rise sufficiently so that the stopper 70 is immediately held in place by water 22 in the bathtub 10 for example. In either event, a pressure differential (e.g. water pressure from water 22 and/or suction/vacuum) and/or buoyancy holds the stopper 70 in place. Also in either event, at the time the overflow openings 40 and 42 are blocked, a person is present to ensure that the bathtub 10 does not overflow.

As illustrated in FIG. 2, when the water level 24 in the bathtub 10 subsequently drops below the cover plate 20, the stopper 70 falls away from the cover plate 20 and from the overflow openings 40 and 42, thus ensuring that the stopper 70 must again be manually applied, as described just above, the next time the bathtub 10 is filled. Accordingly, the stopper 70 can be characterized as “automatically releasing”.

Many additional implementations are possible for blocking or impeding the flow of water through the overflow drain of a bathtub. As one example and with reference to FIGS. 7-8, stopper 100 may be used for blocking or impeding the flow of water through overflow drain opening 18 of bathtub 10 that either includes cover plate 20 as described previously or cover plate 120 as shown in FIG. 10. Cover plate 120 is of simple shape, being in the outline of a circular disc with a rounded upper edge. Cover plate 120 has annular portion 122 surrounding domed portion 124 which axially projects from the internal perimeter of annular front portion 122 away from end wall 16 of bathtub 10 when installed as shown in FIG. 10. Domed portion 124 includes central aperture 126 for attachment of screw 128 (FIG. 10), as well as a plurality of overflow openings 130 disposed in a symmetrical fashion adjacent aperture 126 through which bathtub overflow water enters the space behind cover plate 120 and drain opening 18. Intermediate portions 132 separate openings 130. When installed, an edge of cover plate 120 contacts either bathtub end wall 16 or a circular mounting plate (not shown).

Stopper 100 includes a circular body including disc-shaped front portion 102 surrounded by annular portion 104. Annular portion 104 includes internal arcuate surface 106, which may be a concave surface, as well as an external, partially arcuate surface, which may be a partially concave surface. Stopper 100 also includes internal cover plate cavity 108 defined by disc-shaped front portion 102 and annular portion 104. Stopper 100 additionally includes handle 110 attached to an external portion of annular portion 104, opposite internal arcuate/concave surface 106, and terminating in aperture 112 for attachment of tether 72 or some stopper holder. Stopper 100 may be made from a soft pliable plastic, rubber, or rubber-like material, such as a vinyl, and may have a neutral or slightly positive or negative buoyancy in water.

Disc-shaped front portion 102 and annular portion 104 contact cover plate 120 to block or impede the flow of water through the overflow drain, aided by the pliable nature of the material forming stopper 100. Thus, depending on the precise shape of cover plate 120 and openings 130, at least a partial seal is formed between contacting portions of internal concave/arcuate surface 106 and the internal surface of disc-shaped front portion 102, on the one hand, and portions of cover plate 120, on the other hand. As a result, the flow of water through openings 130 and then through drain opening 18 is either blocked or greatly impeded.

Another characteristic of stopper 100 is that when water level 24 in bathtub 10 is above overflow openings 130, stopper 100, as a result of the material of which it is made and its configuration, is held in place by a pressure differential (e.g. water pressure from water 22 and/or suction/vacuum) and/or buoyancy only. In other words, any frictional engagement which may exist is insufficient to hold stopper 100 in place without water 22.

As a result, when bathtub 10 is being filled with water 22, stopper 100 must be deliberately employed at the time when water level 24 just reaches the height of overflow openings 130. This prevents a person from applying stopper 100 to block overflow openings 130 while beginning to fill bathtub 10 with water 22, with the intention of returning to shut off the flow of water 22 into bathtub 10 before bathtub 10 overflows. Many persons do other tasks while bathtub 10 is filling, at least in the initial stages, and accordingly do not simply watch bathtub 10 during the initial stages of a filling operation. If a person is distracted while bathtub 10 is filling and if stopper 100 were to be in place, bathtub 10 could very well overflow.

Accordingly, during use, when water level 24 reaches overflow openings 130 during a filling operation, the person filling the bathtub positions stopper 100 as illustrated in FIG. 9 so as to block overflow openings 130. At that point, one possibility is that the person manually holds stopper 100 in place until such time as water level 24 has sufficiently risen to hold stopper 100 in place for example. Alternatively, the person at that point may simply turn off the flow of water 22 into bathtub 10 and enter bathtub 10. Water displaced by the person's body causes water level 24 to rise sufficiently so that stopper 100 is immediately held in place by water 22 in the bathtub 10 for example. In either event, a pressure differential (e.g. water pressure from water 22 and/or suction/vacuum) and/or buoyancy holds stopper 100 in place. Also in either event, at the time overflow openings 130 are blocked, a person is present to ensure that bathtub 10 does not overflow.

As illustrated in FIG. 10, when water level 24 in bathtub 10 subsequently drops below cover plate 120, stopper 100 falls away from cover plate 120 and from overflow openings 130, thus ensuring that stopper 100 must again be manually applied, as described just above, the next time bathtub 10 is filled. Accordingly, stopper 100 can be characterized as “automatically releasing”.

As another example, a stopper implementation similar to stopper 70, but not including locating bosses 84 and 86, may be used for blocking or impeding the flow of water through the overflow drain of a bathtub. As still another example, a stopper implementation similar to stopper 100, but including locating bosses 84 and 86, may be used for blocking or impeding the flow of water through the overflow drain of a bathtub. As yet another example, a stopper implementation similar to stopper 100, but having a semi-circular body (i.e. a semi-disc-shaped front portion surrounded by a semi-annular portion) with or without locating bosses 84 and 86 may be used for blocking or impeding the flow of water through the overflow drain of a bathtub. Further implementations are within the CLAIMS.

It will be understood that overflow stopper implementations are not limited to the specific components disclosed herein, as virtually any components may be utilized consistent with the intended operation of an overflow stopper implementation for blocking or impeding the flow of water through the overflow drain of a bathtub. Accordingly, for example, although particular bathtubs and bathtub rims, bottoms, end walls, and drain openings, cover plates and cover plate front portions, front annular portions, front domed portions, skirts, perimeters, edges, bottoms, overflow openings, and apertures, spouts, handles, stoppers and stopper front portions, bodies, concave surfaces, cavities, bosses, handles, apertures, and edges, tethers, and other components are disclosed, such components may comprise any shape, size, style, type, model, version, measurement, concentration, material, quantity, and/or the like consistent with the intended operation of an overflow stopper implementation for blocking or impeding the flow of water through the overflow drain of a bathtub. Implementations are not limited to uses of any specific components, provided that the components selected are consistent with the intended operation of an overflow stopper implementation for blocking or impeding the flow of water through the overflow drain of a bathtub.

Accordingly, the components defining any overflow stopper implementation may be formed of any of many different types of materials or combinations thereof that can readily be formed into shaped objects provided that the components selected are consistent with the intended operation of an overflow stopper implementation for blocking or impeding the flow of water through the overflow drain of a bathtub. For example, the components may be formed of: rubbers (synthetic and/or natural); polymers such as plastic, PVC plastic, ABS plastic, vinyl, polycarbonate, polystyrene, polypropylene, nylon, any combination thereof, and/or other like materials; any other suitable material; and/or any combination thereof.

Furthermore, the components defining any overflow stopper implementation may be purchased pre-manufactured or manufactured separately and then assembled together. However, any or all of the components may be manufactured simultaneously and integrally joined with one another. Manufacture of these components separately or simultaneously may involve extrusion, pultrusion, vacuum forming, injection molding, blow molding, resin transfer molding, casting, milling, stamping, cutting, punching, and/or the like. If any of the components are manufactured separately, they may then be coupled with one another in any manner, such as with adhesive, a fastener, any combination thereof, and/or the like for example, depending on, among other considerations, the particular material forming the components.

As described above, overflow stopper implementations are particularly useful in blocking or impeding the flow of water through the overflow drain of a bathtub. However, implementations are not limited to uses relating to blocking or impeding the flow of water through the overflow drain of a bathtub. Rather, any description relating to blocking or impeding the flow of water through the overflow drain of a bathtub is for the exemplary purposes of this disclosure, and implementations may also be used with similar results in a variety of applications for a variety of fluids, such as blocking or impeding the flow of air from exiting out through the overflow drain of a bathtub.

For the exemplary purposes of this disclosure, in describing the use of overflow stopper implementations in blocking or impeding the flow of air from exiting out through the overflow drain of a bathtub, plumbers often are called upon to unclog bathtub drains; i.e. remove hair, soap scum, body oils, and other debris that may be slowing or stopping the bathtub drain. In some instances this involves delivering high-pressure air via a plunger or an air gun down the bathtub drain to force the clog out of the drain. However, the overflow opening(s) associated with the cover plate need to be covered or the high-pressure air will just come out there.

Accordingly, when delivering high-pressure air via a plunger or an air gun down a bathtub drain to force a clog out of the drain, plumbers may employ overflow stopper implementations to cover overflow opening(s) associated with a cover plate to block or impede the flow of high-pressure air from exiting out through the overflow drain. Depending upon the overflow stopper implementation, this may be accomplished by the plumber manually holding the overflow stopper implementation in place or by removably coupling the overflow stopper implementation in place for example. For example, if utilizing stopper 70 on cover plate 20, locating bosses 84 and 86 may be sized to fit tightly within the overflow openings 40 and 42 of cover plate 20. In other words, locating bosses 84 and 86 may provide frictional engagement sufficient to stay removably coupled and block or impede the flow of high-pressure air from a plunger or an air gun from exiting out through the overflow drain.

The implementations and examples set forth herein were presented in order to best explain the present invention and its practical applications and to thereby enable those of ordinary skill in the art to make and use the invention. However, those of ordinary skill in the art will recognize that the foregoing description and examples have been presented for the purposes of illustration and example only. The description as set forth is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the teachings above without departing from the spirit and scope of the forthcoming claims. Accordingly, any components of the present invention indicated in the drawings or herein are given as an example of possible components and not as a limitation. Similarly, any steps or sequence of steps of the methods of the present invention indicated herein are given as examples of possible steps or sequence of steps and not as limitations. 

1. A device for blocking or impeding the flow of water through at least one overflow opening of a bathtub, the device comprising: a stopper configured to be removably held in place by a pressure differential or buoyancy only when water level in the bathtub is above the at least one overflow opening, the stopper comprising a body defining an internal arcuate surface configured to cover the at least one overflow opening.
 2. The device of claim 1, wherein the body is one of a semi-annular body, a semi-circular body, and a circular body.
 3. The device of claim 2, the semi-circular body comprising a semi-disc-shaped front portion surrounded by a semi-annular portion, the semi-annular portion defining the internal arcuate surface.
 4. The device of claim 2, the circular body comprising a disc-shaped front portion surrounded by an annular portion, the annular portion defining the internal arcuate surface, and the disc-shaped front portion and the annular portion defining an internal cavity.
 5. The device of claim 1, wherein the internal arcuate surface is a concave surface.
 6. The device of claim 1, wherein the stopper includes a tether attachment aperture.
 7. The device of claim 6, wherein the tether attachment aperture is defined in a free end of a handle attached to an external portion of the body.
 8. The device of claim 1, wherein the stopper is formed of one of a material which has a negative buoyancy in water, a material which has a neutral buoyancy in water, a material which has a positive buoyancy in water, and vinyl.
 9. An overflow drain and stopper system, the system comprising: an overflow drain comprising an overflow drain opening in a wall of a bathtub and a cover plate over the overflow drain opening, the cover plate comprising at least one overflow opening in one of an annular skirt and a domed portion; and a stopper for blocking or impeding the flow of water through the overflow drain, the stopper comprising a body defining an internal arcuate surface, and the stopper removably held in place by a pressure differential or buoyancy only when water level in the bathtub is above the at least one overflow opening.
 10. The device of claim 9, wherein the body is one of a semi-annular body, a semi-circular body, and a circular body.
 11. The device of claim 10, the semi-circular body comprising a semi-disc-shaped front portion surrounded by a semi-annular portion, the semi-annular portion defining the internal arcuate surface.
 12. The device of claim 10, the circular body comprising a disc-shaped front portion surrounded by an annular portion, the annular portion defining the internal arcuate surface, and the disc-shaped front portion and the annular portion defining an internal cavity.
 13. The device of claim 9, wherein the internal arcuate surface is a concave surface.
 14. The device of claim 9, wherein the stopper includes a tether attachment aperture.
 15. The device of claim 14, wherein the tether attachment aperture is defined in a free end of a handle attached to an external portion of the body.
 16. The device of claim 1, wherein the stopper is formed of one of a material which has a negative buoyancy in water, a material which has a neutral buoyancy in water, a material which has a positive buoyancy in water, and vinyl.
 17. A method for blocking or impeding the flow of water through an overflow drain, the overflow drain comprising an overflow drain opening in a wall of a bathtub and a cover plate over the overflow drain opening, the cover plate comprising at least one overflow opening in one of an annular skirt and a domed portion, the method comprising: covering the at least one overflow opening with a stopper; and removably holding the stopper in place by a pressure differential or buoyancy only when water level in the bathtub is above the at least one overflow opening.
 18. The method of claim 19, wherein covering the at least one overflow opening comprises covering the at least one overflow opening with a stopper having a body defining an internal arcuate surface.
 19. The method of claim 20, wherein covering the at least one overflow opening comprises covering the at least one overflow opening with a stopper having one of a semi-annular body, a semi-circular body, and a circular body.
 20. The method of claim 19, wherein covering the at least one overflow opening comprises covering the at least one overflow opening with a stopper having one of a negative buoyancy in water, a neutral buoyancy in water, and a positive buoyancy in water.
 21. The method of claim 19, wherein covering the at least one overflow opening comprises covering the at least one overflow opening with a vinyl stopper.
 22. The method of claim 19 further comprising tethering the stopper. 